Vacuum coaters

The Agar range of vacuum coating units offers the user a wide choice of options to suit all coating requirements needed in support of SEM and TEM applications. These compact bench-top coating units are built to a high specification and incorporate microprocessor technology.

Basic coating

For routine gold sputtering of SEM samples, the manual sputter coater AGB7340 provides a low cost solution. For high sample throughputs, or occasions where alternative target materials, such as gold/palladium, are required to achieve finer grained coatings, the automatic coating unit AGB7341 should be selected. For microanalytical applications where gold coating may not be appropriate, the carbon coater AGB7367A is ideal. The dual carbon rod source, with unique current feedback control, gives highly reproducible carbon coatings for SEM samples. The pumping system AGB7366 is designed for use with the coating units. It includes an anti-vibration platform, stainless steel bellows connection and vacuum fittings. If both carbon and gold sputtering are required, the dual pumping system AGB7736 with changeover valve can be used to pump two coating units. Where an accurate determination of coating thickness is required, the manual film thickness monitor AGB7348 can be used with all the units. Further automation of the coating process can be achieved by fitting the film thickness monitor with terminator AGB7349 to the automatic sputter coater. With this fitted, sputtering is automatically terminated when the desired pre-set thickness has been reached.

High resolution coating

Preparing samples for examination in an FEG SEM requires fine grained coatings in order to make the most of the greater resolution available. The high resolution coater AGB7234 includes chromium and platinum/palladium targets as standard. The turbomolecular drag pump provides the high vacuum and high volume gas handling necessary for sputtering these materials. The rotary planetary stage and film thickness monitor are also included as standard, to ensure that coating thickness can be kept to a minimum to prevent charging.

High vacuum carbon coating and metal evaporation

For carbon coating of mounted, polished samples for microprobe analysis and back-scatter applications, the SEM turbo coater AGB7230 should be used. The higher vacuum gives a fine continuous carbon layer and the optional rotary planetary stage ensures a uniform coating over a number of samples. The SEM turbo coater should also be used for carbon coating of highly contoured or porous samples; tilting the rotary planetary stages ensures that all facets of the specimen are evenly coated and specimen charging can be eliminated with the minimum thickness of coating. The TEM turbo coater AGB7232 has been designed to provide all the facilities required for TEM and in the basic form can be used to make thin carbon support films or for coating grids. The auxiliary power supply allows a range of other accessories to be easily fitted. These include a metal evaporation source, aperture cleaning and glow discharge for the hydrophilisation of grids. A rotary shadowing table is also available as an accessory.